Assoc. Prof. Karlo Lelas, Ph.D.

Position:

• Associate Professor of Physics at the Faculty of Textile Technology University of Zagreb (Department of Fundamental Natural and Technical Sciences)

Fields of interest:

• Classical physics: vibrations of single and multi degrees of freedom systems, the optimal damping of vibrations, alternative approaches to the analysis of the dynamics of classical systems

• Quantum physics: interacting quantum systems, synthetic gauge fields

Selected publications:

• K. Lelas, D. Jukić, An alternative approach to several important systems in classical mechanics: energy factorization, European Journal of Physics 47, 035012 (2026)
• K. Lelas, N. Poljak, Driven damped harmonic oscillator revisited: energy resonance, European Journal of Physics 47, 015015 (2026)
• K. Lelas, R. Pezer,  The amplitude decay of a harmonic oscillator damped simultaneously by weak linear and nonlinear damping forces, European Journal of Physics 46, 045001 (2025)
• K. Lelas, Optimal damping adapted to a set of initial conditions, Journal of Sound and Vibration 609, 119076 (2025)
• K. Lelas, I. Nakić, Optimal damping of vibrating systems: Dependence on initial conditions, Journal of Sound and Vibration 576, 118303 (2024)
• K. Lelas, N. Poljak, D. Jukić, Damped harmonic oscillator revisited: The fastest route to equilibrium, American Journal of Physics 91, 767–775 (2023) 

• K. Lelas, O. Čelan, D. Prelogović, H. Buljan, and D. Jukić, Modulation instability in the nonlinear Schrödinger equation with a synthetic magnetic field: Gauge matters, Phys. Rev. A 103, 013309 (2021).

• K. Lelas, N. Drpić, T. Dubček, D. Jukić, R. Pezer, and H. Buljan, Laser assisted tunneling in a Tonks-Girardeau gas, New J. Phys. 18, 095002 (2016).

• T. Dubček, K. Lelas, D. Jukić, R. Pezer, M. Soljačić, and H. Buljan, The Harper-Hofstadter Hamiltonian and conical diffraction in photonic lattices with grating assisted tunneling, New J. Phys. 17, 125002 (2015).

• K. Lelas, T. Ševa. H. Buljan, and J. Goold, The pinning quantum phase transition in a Tonks_Girardeau gas: diagnostics by ground state fidelity and Loschmidt echo, Phys. Rev. A 86, 033620 (2012).

• K. Lelas, D. Jukić, and H. Buljan, Ground state properties of a one-dimensional strongly-interacting Bose-Fermi mixture in a double well potential, Phys. Rev A 80, 053617 (2009).

Reviewer for:

• Physica Scripta
• European Journal of Physics
• American Journal of Physics

Short Bio:

Karlo Lelas received a master’s degree in physics from the University of Zagreb in 2007 and defended his PhD thesis at the same university in 2012 (supervisor Hrvoje Buljan). In the period from 2007-2015 he was a scientific novice and teaching assistant at Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture (FESB) at University of Split. During this period, he worked in two fields: (i) theoretical physics of strongly interacting one-dimensional quantum systems, and (ii) experimental elementary particle physics. He started his work as a scientific novice in the field (ii) but with time he focused on the field (i), in which he defended his PhD theses. 

KL was promoted to the rank of Associate Professor of Physics at the University of Zagreb in 2026. He teaches General Physics and Classical Mechanics. He is a collaborator of the Center of Excellence for Quantum and Complex Systems and Representations of Lie Algebras (QuantiXLie) at the Faculty of Science of the University of Zagreb.